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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Hypoxemia is associated with mitochondrial DNA damage and gene induction. Implications for cardiac disease 总被引:24,自引:0,他引:24
M Corral-Debrinski G Stepien J M Shoffner M T Lott K Kanter D C Wallace 《JAMA》1991,266(13):1812-1816
992.
Clinical decision making: from theory to practice. The individual vs society. Resolving the conflict 总被引:1,自引:0,他引:1
Eddy argues for reform of the American health care system. In seeking health coverage, he explains, there are two positions: the first, that of society, seeks to allocate services efficiently; the second, that of the patient, seeks to optimize individual patients' care. Using his illustration of breast cancer coverage from a previous JAMA article (1991 Mar 20; 265 (11): 1446+), Eddy contends that a tradition of decision-making from the second position is the root of present health care inefficiencies. Eddy's ideal would be complete information to physicians and patients about service costs, benefits, and financial feasibility, and an agreed-upon standard of fair resource allocation, based on the threshold of a specific measure of benefit per resource. To approach this ideal, he concludes, we must recognize the problem, pursue education about service costs and benefits and people's desires of the system, and identify and review services that presently are inefficiently utilized. 相似文献
993.
Thiazide diuretics may preserve bone mass and prevent elderly women's osteopenic fractures, but studies have not distinguished between thiazide preparations or examined former users. We performed a case-control study looking at thiazide use and subsequent hip fracture in postmenopausal female members of the Framingham Study cohort. Cases who had experienced a first hip fracture (n = 176) were compared with age-matched controls (n = 672). Results showed a modest protective effect of any recent thiazide use (not significant). However, recent pure thiazide users experienced significant protection against fracture (adjusted odds ratio, 0.31; 95% confidence interval, 0.11 to 0.88), whereas recent users of combination drugs containing thiazides experienced no protection (adjusted odds ratio, 1.16; 95% confidence interval, 0.44 to 3.05). Combination drugs generally contained only 25 mg of hydrochlorothiazide, suggesting that the small amount of thiazide was insufficient to preserve bone mass. Former thiazide users were not protected against fracture. In sum, recent pure thiazide use in women protects against hip fracture. 相似文献
994.
995.
In 1984, in addition to its standard traditional curriculum, Rush Medical College (Chicago, Ill) developed a Socratic problem-based method of teaching basic science material called the alternative curriculum. As part of an evaluation of this new curriculum, students in the two curricula were compared using three traditional measurements: (1) test scores from the National Board of Medical Examiners, Part I; (2) test scores from the National Board of Medical Examiners, Part II; and (3) performance on an oral examination. Alternative curriculum students did not differ significantly from their traditional curriculum classmates on National Board of Medical Examiners, Part I and Part II total scores, although their subset scores on Part I did tend to be lower, reaching significance in one subset area. Differences in performance favoring the traditional curriculum were primarily seen in the early years of the program. Alternative curriculum students in the class matriculated in 1987 scored significantly higher in three of five categories on the oral examination. 相似文献
996.
997.
998.
I D Johnson 《JAMA》1991,265(3):407-8, 410-1
999.
Complications associated with central venous catheters inserted in critically ill neonates 总被引:2,自引:0,他引:2
V Hruszkewycz P C Holtrop D G Batton R S Morden P Gibson J D Band 《Infection control and hospital epidemiology》1991,12(9):544-548
OBJECTIVE: To assess the incidence and spectrum of complications associated with central venous catheter (CVC) placement in the critically ill infant. DESIGN: A prospective study of all babies hospitalized in a neonatal intensive care unit (NICU) from January 1989 to December 1989. Potential risk factors associated with infection were evaluated by a case-control comparison. SETTING: Conducted at a university-affiliated, tertiary care community hospital. PATIENTS: Neonates requiring intensive care and a central venous catheter. Controls consisted of noninfected babies. RESULTS: Of 263 critically ill neonates, only 13 (4.9%) required a CVC insertion. Seventeen CVCs were placed in these 13 neonates for a total duration of 600 days (median, 32 days/cannula). Fifteen (88%) of these cannulas had one or more complications during its catheter life including dislodgement or leakage (53%), occlusion or thrombosis (47%), infections (29%), or minor bleeding (12%). Five babies (29%) developed 6 episodes of bloodstream infection including 3 sporadic cases due to Staphylococcus epidermidis and a cluster of fungemia due to Malassezia furfur associated with lipid emulsion therapy. Infants with a CVC-associated infection were a younger gestational age (24 weeks versus 32 weeks, p = .04) and weighed less at birth (580 g versus 1285 g, p = .02). The overall rate of bloodstream infection was one episode per 100 days of catheter use. CONCLUSIONS: CVCs may be lifesaving to a critically ill neonate, but complications occur frequently. Use must be restricted to infants in whom alternate delivery routes of intravenous therapy or support are otherwise unavailable. 相似文献
1000.